Sesquiterpene dimers are mainly found in the Asteraceae family. However, conflicting reports on the structures of these compounds can be found in the literature. Herein, we describe ten sesquiterpene dimers isolated from the flowers of Inula japonica, including configurational revisions of japonicone H (1-1), japonicone D (2-1), inulanolide A (4-1), japonicone X (5-1), and inulanolide F (5-2) to compounds 1, 2, 4, and 5, respectively. Five new related metabolites (3 and 6-9) are also described. Application of GIAO NMR/DP4+ analyses and ECD/OR calculations enabled us to revise the absolute configurations of an additional 13 sesquiterpene dimers isolated from plants of the genus Inula. Compounds 1, 2, 4, and 6 exhibited inhibition of nitric oxide production in lipopolysaccharide activated RAW264.7 macrophages with IC50 values of 4.07-10.00 mu M.
Myocardial fibrosis is the fundamental remodeling process in myocardial ischemia (MI) and also the major contributor of heart failure and death. Tanshinol (Danshensu in Chinese, DSS), a major ingredient of salvia mitiorrhiza Bunge (Lamiaceae) root, exerted significant cardio protection effects. In this study, we aimed to identify the action target and then uncover the mechanism of DSS alleviating myocardial fibrosis. The pharmacological activities of DSS protecting ischemic cardiac was assessed and the myocardial proteomics was carried out. To identify the target of DSS, a cellular thermal shift assay combined with LC-MS identification was conducted. Surface plasmon resonance assay, molecular dynamics simulation and pharmacological and molecular biology approaches were adopted to explore the action mechanisms of DSS. Our results revealed that DSS effectively alleviated MI-induced left ventricle dysfunctions and the increasements of circulating myocardial markers. Besides, DSS significantly reversed the proteomic profile related to myocardial fibrotic processes and the ERK2 was identified as a crucial cellular target of DSS. DSS abated the temperature-dependent denaturation of ERK2 in a dose-dependent manner and the KD value of DSS and ERK2 was 60.19 μM. After Ang II stimulation, DSS suppressed the phosphorylation of Thr188 rather than the classic residues in TEY motif. DSS interfered the ERK2 homo-dimerization and then blocked the intermolecular autophosphorylation at Thr188 site. Thereout, DSS inhibited the nuclear translocation of ERK2 and the expression of downstream fibrotic biomolecules. Collectively, our results demonstrated that DSS targeted ERK2 and suppressed the intermolecular autophosphorylation at Thr188 residue, thus protecting ischemic myocardia from fibrosis remodeling.
Ethnopharmacological relevance: Cimicifuga foetida L. is a well-established traditional Chinese medicine with heat-clearing and detoxifying effects and has good therapeutic effect on oral mucosal ulcer and pharyngitis. The rhizome of this herb is rich in triterpenoid glycosides, including 23-O-acetylshengmanol-3-o-alpha-L-arabinoside (DA).Aim of the study: Whether and how DA attenuates acute lung injury (ALI) are unclear. Accordingly, we focused on its anti-inflammatory effects and underlying molecular mechanisms in lipopolysaccharide (LPS)-stimulated ALI mice and RAW264.7 cells.Materials and methods: The model of ALI mice was established by exposed intratracheal instillation of LPS. Lung pathological changes were evaluated by hematoxylin and eosin staining. Pulmonary function was assessed by whole-body plethysmography. Total protein content in bronchoalveolar lavage fluid (BALF) was detected by bicinchoninic acid method. Wet/dry lung ratio was used to evaluate the degree of pulmonary edema in mice. The levels of pro-inflammatory mediators were measured using enzyme-linked immunosorbent assay. The relative expression of pro-inflammatory gene mRNA was examined by RT-qPCR. The expression of inflammatory-related proteins was detected by Western blot. RAW264.7 cells were used to test the anti-inflammatory effects of DA in vitro. Cytotoxicity was assessed using a MTT assay. Nitric oxide production was measured by Griess assay. The production and expression of inflammatory mediators and the protein levels of inflammatory signaling molecules in the NF-Kappa B and MAPK pathways were measured. Furthermore, immunofluorescence staining was used to analyze the expression of p-I Kappa B alpha, p-ERK, and p-p38 in lung macrophages and the nuclear translocation of NF-Kappa B p65 and AP-1 in cells.Results: DA evidently alleviated histopathological changes and ameliorated pulmonary edema. Moreover, DA could reduce excessive inflammatory reaction in lung tissue as manifested by the reduction of proinflammatory mediators (IL-1 beta, IL-6, TNF-alpha, MCP-1, iNOS, and COX-2) in BALF, serum, and lung tissues. Further, DA inhibited the activation of the NLRP3/caspase-1 pathway in the lung. DA reduced the production and expression of the proinflammatory mediators above in RAW264.7 cells. Mechanistically, DA remarkably blocked the nuclear translocation of NF-Kappa B p65, suppressed I Kappa B alpha phosphorylation, and markedly reduced the nuclear translocation of AP-1 and the phosphorylation of ERK and p38.Conclusions: The findings demonstrated that DA exerts anti-inflammatory effects in LPS-stimulated ALI mice and macrophages by downregulating the NLRP3/caspase-1 signaling pathway in lung tissue and the I Kappa B/NF-Kappa B and MAPKs/AP-1 pathways in macrophages, suggesting that DA may be promising in ALI treatment.